1. Field of the Invention
Embodiments of the invention relate generally to superconducting magnet assemblies and fabricating methods.
2. Description of the Prior Art
Superconducting magnets comprise superconducting coils conducting electricity without resistance as long as the magnets are maintained at a suitably low temperature, which is referred to as “superconducting temperature” hereinafter. Accordingly, when a power source is initially coupled to the superconducting coils, electrical current continues to flow through the coils even after the power is removed resulting in a strong magnetic field being maintained. Superconducting magnet are used in, for example, a Magnetic Resonance Imaging (MRI) systems, to generate a strong, uniform magnetic fields within which a patient or other subject is placed.
A superconducting magnet assembly usually comprises several superconducting coils wound on a bobbin for example, and a cooling system for cooling the superconducting coils at the superconducting temperature. When an electrical current is applied to the magnetic coils, known as a ramp-up, magnetic forces act on the magnetic coils, and the coils have a tendency to move and deform under the forces. When the current is removed from the coils, the forces diminish, and the coils will tend to return to their original positions. A small shift in the relative position of the coils can significantly impact the quality of the magnetic field produced by the magnet. The magnetic forces exert stresses and strains on the coils, excessive stresses or strains may cause the coil to break or become damaged. Further, excessive stresses or strains may cause cracking or frictional movements in the coils, which raise the coil temperature to exceed the superconducting temperature and quench the magnet. Accordingly, mechanical support arrangements are needed for securing the coils in place, and for bearing strains and stresses on the coils which are generated by the magnetic forces.
One conventional mechanical support arrangement comprises a plurality of support members mechanically securing the corresponding magnetic coils on the bobbin, which adversely make the assembly very complicated and bulky.
It is desirable to have a different and a simpler superconducting magnet assembly and method with mechanical support arrangements for superconducting coils.